Rodw, follow the link above, it is all there with instructions and more, but it is not for THCAD, it is for usual THC with UP/DOWN/ARCOK signals. I did quite some work on it, but whoever made that config deserves a lot of credit for implementing everyrhing in HAL. So it does not need anything related to Z axis, nor touch off or anything else. All is automated with an M3.
I use it on several (6) machines for quite some time now, it is awesome.

Do not change the file names, or if you do change them, change the appropriate entries in the ini file.
And you have the limit switch ( in this case the probe switch ) wired to pin 13 in hal, not pin 15.
For that BOB you might need to add the enable to pin 14 and edit the thc.hal for torch on from pin 09 to pin 17.
When you power on the drives, do the motors lock can you move them by hand?